Tuning of a kinematic relationship between members

ABSTRACT

Described herein is a device comprising members in a kinematic relationship. The kinematic relationship is at least partially governed by at least one magnetic flux interaction that, in effect, may provide a tunable resistance to movement, changing the rate of relative movement between the members. In one embodiment, the device comprises a first member in a kinematic relationship with at least one further member to form a system. The system moves within a limited range of motion and the system interacts when an external energizing force is imposed on the system causing the members to respond due to their kinematic and dynamic characteristics and thereby creating relative motion between the members. The trigger member is coupled to the at least the first member and moves in response to a pre-determined system movement. When the trigger member moves, the trigger member imposes a braking action on the system or a member or members thereof. The speed and/or intensity of the braking action imposed by the trigger member on the system or a member or members thereof is controlled by the trigger member rate of movement. This rate of movement is in turn governed by a magnetic flux interaction between the trigger member and the at least one first member causing formation of a magnetically induced eddy current force between the parts.

RELATED APPLICATIONS

This application derives priority from New Zealand patent applicationnumber 627633 incorporated herein by reference.

BACKGROUND Technical Field

Described herein is a device comprising members in a kinematicrelationship, the kinematic relationship at least partially governed byat least one magnetic flux interaction that, in effect, may provide atunable resistance to movement, changing the rate of relative movementbetween the members.

Description of the Related Art

Eddy current formation may be used in a variety of ways to adjust therate of movement of a member. Various apparatus exist, for example inabseiling, to control the descent of a climber or for example, inpersonal protective equipment scenarios to prevent an injury causingfall. Other applications that use eddy current generation are incontrolling pay-out of line in trains, cable cars, zip line devices androller coasters.

One art device is published as US2012/0055740. This device utilizes arotor assembly with arms that move relative to the rotor. The armsthemselves may be conductive or magnetic or may have conductive ormagnetic members attached thereto. When a rotational force is applied tothe rotor, the arms move outwards from a central axis via centrifugalforce and into a magnetic (or conductive) field. As the arms movethrough the field, eddy currents are generated, the strength of which isdependent on the speed of rotation. As the speed of rotation reduces,the arms are drawn back towards the axis of rotation via springs and/ora reduced centrifugal force acting on the arms. This device is widelyused and provides an excellent means of changing the relative speed ofparts.

One aspect of the above apparatus is that control on the speed ofactivation of the braking effect caused by movement of the arms into themagnetic field can only be tuned by adjusting a few variables includingbias strength, arm weight (and hence inertia) and pivot axisplacement—influenced by either the degree of offset from a center ofmass of the arm and/or the degree of offset of the pivot axis from therotor axis.

Tuning movement of the arms once movement commences via an additionalinput may also be useful depending on the end application of the deviceor at least it provides the public with a choice.

Further aspects and advantages of the device will become apparent fromthe ensuing description that is given by way of example only.

BRIEF SUMMARY

Described herein is a device comprising members in a kinematicrelationship, the kinematic relationship at least partially governed byat least one magnetic flux interaction that, in effect, may provide atunable resistance to movement, changing the rate of relative movementbetween the members.

In a first aspect, there is provided a device comprising:

at least one first member in a kinematic relationship with at least onefurther member to form a system, the system moving within a limitedrange of motion and wherein the system interacts when an externalenergizing force is imposed on the system causing the members to responddue to their kinematic and dynamic characteristics and thereby creatingrelative motion between the members;

at least one trigger member coupled to the at least the first memberthat moves in response to a pre-determined system movement and, when theat least one trigger member moves, the at least one trigger member or apart thereof imposes a braking action on the system or a member ormembers thereof; and,

wherein the speed and/or intensity of the braking action imposed by theat least one trigger member on the system or a member or members thereofis controlled by the at least one trigger member rate of movement andthis rate of movement is in turn governed by a magnetic flux interactionbetween the at least one trigger member or a part thereof and the atleast one first member or a part thereof causing formation of amagnetically induced eddy current force between the at least one triggermember or a part thereof and the at least one first member or a partthereof.

In a second aspect, there is provided a line dispensing deviceincorporating at least one device substantially as described above.

In a third aspect, there is provided a passenger seat restraintincorporating at least one device substantially as described above.

In a fourth aspect, there is provided a transmission drive incorporatingat least one device to engage a rotational drive substantially asdescribed above.

In a fifth aspect, there is provided a linear guided lifelineincorporating at least one device substantially as described above.

Numerous other applications of the device may also be possible asfurther outlined in the description below.

One advantage of the above device includes the ability to control therate of movement prescribed by the kinematic relationship. In addition,a further advantage of the device is to also influence the kinematicrelationship once movement commences. The magnitude of the resistance tomovement may be varied in a consistent manner as the members move or ina stepped or otherwise varied manner. Tuning in this way may have theeffect of avoiding unwanted activation or slowing the speed ofactivation of, for example, a brake engagement.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Further aspects of the device will become apparent from the followingdescription that is given by way of example only and with reference tothe accompanying drawings in which:

FIG. 1 illustrates a side view of one embodiment of a device with thetrigger and first members in a magnetic relationship;

FIG. 2 illustrates an exploded perspective view of the trigger and firstmembers in the embodiment described in FIG. 1;

FIG. 3 illustrates a side view of an alternate embodiment incorporatinga rod shaped trigger member;

FIG. 4 illustrates a side view of an alternate embodiment incorporatinga sliding first member and a pivoting trigger member pawl;

FIG. 5 illustrates a side view of an alternative embodiment to FIG. 4incorporating a rod shaped first member;

FIG. 6 illustrates a side view of an alternative embodiment with asecond member and latching member;

FIG. 7 illustrates an exploded perspective view of an alternativeembodiment using a latching member;

FIG. 8 illustrates a side view of a further alternative embodiment witha second member and stationary first member pivotally attached to atrigger member; and

FIG. 9 illustrates a side view of a further alternative embodiment witha second member and stationary first member attached to a linearlytranslating trigger member.

DETAILED DESCRIPTION

As noted above, described herein is a device comprising members in akinematic relationship, the kinematic relationship at least partiallygoverned by at least one magnetic flux interaction that, in effect, mayprovide a tunable resistance to movement, changing the rate of relativemovement between the members.

For the purposes of this specification, the term ‘about’ or‘approximately’ and grammatical variations thereof mean a quantity,level, degree, value, number, frequency, percentage, dimension, size,amount, weight or length that varies by as much as 30, 25, 20, 15, 10,9, 8, 7, 6, 5, 4, 3, 2, or 1% to a reference quantity, level, degree,value, number, frequency, percentage, dimension, size, amount, weight orlength.

The term ‘substantially’ or grammatical variations thereof refers to atleast about 50%, for example 75%, 85%, 95% or 98%.

The term ‘comprise’ and grammatical variations thereof shall have aninclusive meaning—i.e., that it will be taken to mean an inclusion ofnot only the listed components it directly references, but also othernon-specified components or elements.

The term ‘energizing force’ and grammatical variations thereof refers toa force that acts to impose a rate of movement on an object.

The term ‘dynamic’ and grammatical variations thereof in the context ofdevice or device part movement refers to forces induced by mechanicalmeans.

In a first aspect, there is provided a device comprising:

at least one first member in a kinematic relationship with at least onefurther member to form a system, the system moving within a limitedrange of motion and wherein the system interacts when an externalenergizing force is imposed on the system causing the members to responddue to their kinematic and dynamic characteristics and thereby creatingrelative motion between the members;

at least one trigger member coupled to the at least the first memberthat moves in response to a pre-determined system movement and, when theat least one trigger member moves, the at least one trigger member or apart thereof imposes a braking action on the system or a member ormembers thereof; and,

wherein the speed and/or intensity of the braking action imposed by theat least one trigger member on the system or a member or members thereofis controlled by the at least one trigger member rate of movement andthis rate of movement is in turn governed by a magnetic flux interactionbetween the at least one trigger member or a part thereof and the atleast one first member or a part thereof causing formation of amagnetically induced eddy current force between the at least one triggermember or a part thereof and the at least one first member or a partthereof.

In one embodiment, the at least one trigger member may comprise amagnetic part or parts that interact with a conductor part or parts onthe at least one first member. Alternatively, the at least one triggermember may comprise a conductor part or parts that interact with amagnetic part or parts on the at least one first member.

The kinematic relationship between the system movement and the at leastone trigger movement may be a non-linear response. The rate of movementof the at least one trigger member relative to the first member may slowas relative motion occurs. Alternatively, the rate of movement of the atleast one trigger member relative to the first member may speed up asrelative motion occurs. Further, the rate of movement of the at leastone trigger member relative to the first member may cycle at least oncebetween slower and faster relative motion. In one embodiment, acomparatively rapid change in rate of movement of the members may occurwhen the at least one trigger member and at least one first member movesufficiently far apart to cause a reduction in magnetic flux interactionbetween the members. For example, when the magnetic flux terminates thetrigger and first members are able to move freely with no eddy currentinduced resistance. The transition from resistance to no resistance maybe abrupt leading to a rapid change in rate of movement as noted above.

The device action may be further characterized by a variable andpre-determined rate of motion of the trigger member relative to thefirst member, the rate being determined by tuning the magnetic fluxbetween the members. By way of example, the comparative rate of movementbetween the members may vary from fast, to slow, to moderately fast,before the members move apart and the eddy current induced forcedissipates altogether.

Relative movement between the system and the at least one trigger membermay be delayed until the pre-determined system movement occurs.

The system braking action imposed by the at least one trigger member ora part thereof may be caused by: latching, friction force, magneticforce interactions, and combinations thereof.

The rate at which the at least one trigger member moves relative to theat least one first member may be tuned by varying the resulting eddycurrent force between the at least one trigger member and the at leastone first member.

The magnetically induced eddy current force may be tuned by varying atleast one of:

(a) the magnetic element surface area on or within the at least onetrigger member or at least one first member;

(b) the conductive region on or within the at least one trigger memberor at least one first member;

(c) the proximity of at least one magnetic element and at least oneconductive region on the at least one trigger member and at least onefirst member;

(d) the geometry and/or magnetic properties of the at least one magneticelement on or within the at least one trigger member or at least onefirst member;

(e) the geometry and/or electrical properties of the at least oneconductive element on or within the at least one trigger member or atleast one first member;

(f) and combinations thereof.

For example, the trigger member may include a magnetic element, themagnetic strength varying along the direction of travel. As the triggermember moves relative to the first member, the magnetic flux varies andtherefore the eddy current induced force varies along the prescribedpath of movement of the members.

As should be appreciated from the above, the members may take variousshapes or weights, factors that influence the activation and/or rate ofmotion of the member or members during movement. The interaction may forexample be continuous across a trigger and/or first member length orspaced apart or of varying dimensions to thereby adjust the fluxoccurring. The interacting portion of the trigger or other members maybe the whole member or only a portion thereof. Where only a portion ofthe member interacts, the location of the interacting portion either onthe exterior, interior or part of the member, can be altered.

The at least one trigger member and at least one first member may bepositioned so that an immediate magnetically induced eddy current forceinduction occurs as soon as relative movement occurs between themembers. In effect this means that when in an at rest position, the atleast one trigger member and at least one first member are at least inpart in a magnetic relationship together. As noted above however, theeddy current induced force may be tuned and, for example, the magneticflux interaction may only commence after a degree of movement of themembers and the above example should not be seen as limiting.

Movement of the trigger member described above may be direct—that is thetrigger member moves directly due to the energizing force. The triggermember may instead move indirectly or by proxy at least in part due tothe energizing force causing at least one additional mechanical part orforce dynamic to move or interact with the trigger member and therebysubsequently causing motion of the trigger member. Indirect means may bea dynamic force transfer via another part such as a coupling or gear ora centrifugal force being imposed on the trigger member by direct forceon another part. Indirect or proxy force transfer may have the advantageof being able to amplify the energizing force.

Static or dynamic positional and/or strength adjustment of the point ofaction of the eddy current induced force may also be completed by:

(a) adjusting the position of the magnetic element or conductive regionon the trigger member as the trigger member or first member moves;and/or,

(b) adjusting the position of the magnetic element or conductive regionon the first member as the trigger member or first member moves.

By way of example, the trigger member may comprise a slot and a portionof the trigger member comprising the magnetic element or conductiveregion moves within the slot as the trigger member as a whole moves onapplication of the energizing force. This additional means of adjustingmovement may be useful to further alter the force dynamics and hence theway the parts interact. For example, in a rotary movement embodimentwhere the trigger member induces an eddy current drag force on overallsystem movement, positional adjustment may affect both the eddy currentdrag force and position which in turn may alter the resisting torque onthe trigger member. In a linear movement embodiment, positionaladjustment might affect the eddy current force generated.

Relative movement between the trigger member and additional member ormembers may be frictionless. Magnetic forces such as the induced forcenoted above and any subsequent forces acting on the trigger member mayavoid friction contact. This may be useful to minimize mechanicalwearing on the parts.

In one embodiment, movement between the parts may be predominantlygoverned by dynamic forces. The device may be free of liquid fluid withall movement between the parts due to dynamic forces. Alternatively, thedevice may have some liquid fluid present but the predominant energizingforce on the device members may be dynamic force. Liquid based systemsutilizing magnetics to alter kinematic relationships exist but thesedevices differ to that described herein in that that are oftenbi-stable—that is, the parts are only stable in two positions. Inaddition, movement predominantly or wholly relies on a force or pressurebuild up from the liquid fluid as opposed to dynamic forces. Liquidbased devices also have inherent difficulties associated with sealingthe liquid and more regular maintenance being required to ensurereliable running.

As may be appreciated from the above, the at least one trigger memberand at least one first member have a magnetic flux interaction leadingto magnetically induced eddy current forces. The magnetic fluxinteraction may be provided by use of at least one magnetic elementlocated on or within the at least one trigger member interacting with anelectrically conductive region either on or within the at least onefirst member. Alternatively, the at least one magnetic flux interactionmay be provided by use of at least one magnetic element located on orwithin the at least one first member interacting with a conductiveregion either on or within the trigger member. As should be appreciated,a wide variety of configurations may be undertaken to achieve the aboverelationships which assists with making the device very flexible as toexact design. In one embodiment, the whole trigger member may bemagnetic or conductive and similarly, the whole first member may bemagnetic or conductive. Alternatively, parts or regions of either membermay be magnetic or conductive. Designs of member may also integrate theability to remove and replace magnetic elements and/or conductiveelements. Additionally, it should be appreciated that the term‘conductive’ in the context of the above described magnet relationshipsrefers to a material that a magnet interacts with that is electricallyconductive. Further, the material may be ferromagnetic, or the materialmay be paramagnetic. The term ‘conductive’ should not be seen aslimiting in terms of magnetic characteristics.

In one alternative embodiment, the device may include at least onesecond member independent to the at least one first member, the secondmember magnetically interacting with the at least one trigger memberabout at least a part of the at least one trigger member outside an areaoverlapping the at least one first member. This second member may be aseries of magnets or conductive members and, when the trigger membermoves into a region complementary to the second member, an eddy currentinduced force occurs between the trigger and second members. In oneexample, the second member may be stationary. Alternatively, the secondmember may move at a different relative speed to the at least onetrigger member either in the same direction as the trigger member (butdifferent speed) or, in an opposing direction.

In one variation on the above embodiment, the at least one first membermay be fixed and the at least one trigger member moves on application ofthe energizing force, the movement of the at least one trigger memberbeing urged by at least partial magnetic interaction with the at leastone second member and, wherein movement of the at least one triggermember then induces a magnetic flux interaction between the at least onetrigger member and at least one first member. The kinematic relationshipin this variation may be prescribed by the at least one trigger membermoving pivotally relative to the at least one first member.Alternatively, the kinematic relationship in this variation may beprescribed by the at least one trigger member moving via an independenttranslational path relative to the at least one first member.

In a further alternative, the at least one trigger member may engagewith a further latching member or members upon relative movement of theat least one trigger member and at least one first member. Engagement ofthe trigger member and latching member may result in no further relativemotion between the first member and the latching member. This latchingmember may be useful to constrain movement of the kinematicrelationship. The engagement may be releasable so as to re-set thedevice for further movement.

The at least one trigger member and the at least one first member orparts thereof may be approximately adjacent to each other.

The magnetic flux interaction may be at least partially orthogonal tothe direction of relative motion between the at least one trigger memberand at least one first member. In one embodiment, the members lie in thesame plane adjacent each other and, when an energizing force is applied,the members move past each other but remain in the same plane relativeto each other. A magnetic field or fields may extend at right angles tothe member movement. As may be appreciated, whilst fully orthogonalplacement may be optimal, other planar angles may also achieve the sameor similar outcomes.

The trigger member may be an arm shaped member that rotates about anaxis when the pre-determined system movement occurs. The kinematicrelationship may be at least in part prescribed by the at least onetrigger member being pivotally attached to the at least one first memberabout an axis of rotation. The axis of rotation may be positioned sothat movement of the first member causes rotational movement of the atleast one trigger member about the axis of rotation. Movement of the atleast one trigger member about the axis of rotation may rotate at leastpart of the at least one trigger member outside the area bound by the atleast one first member. This kinematic relationship minimizes the numberof parts needed yet confers a useful movement path. The pivot attachmentmay be by use of a mechanical fastener or fasteners, bearings or otherknown components. Movement of the member or members may be constrainedwithin a predetermined range by use of a stop or other means to limitmovement.

In one specific embodiment, movement of the at least one first member onapplication of the energizing force may be rotational movement. In thisembodiment:

-   -   The at least one first member may be a pawl or arm shaped member        or members that are mechanically linked to a first member that        is a rotor which rotates on application of the energizing force.    -   The at least one trigger member may be positioned so that part        of the at least one trigger member moves outside the region        bound by the rotor on application of a sufficiently large        energizing force.    -   The at least one trigger member may be pivotally attached to the        rotor about a pivot axis offset from the rotor axis.

The above embodiment may be useful to minimize the overall size of adevice particularly where space does not allow for a linear track. Theabove device and mechanism may be integrated into a device similar tothat described in US2012/0055740.

The at least one trigger member may alternatively be a rod shaped memberthat moves in a linear direction when the pre-determined system movementoccurs. As noted, the kinematic relationship may be at least in partprescribed by the at least one trigger member moving via an independenttranslational path relative to the at least one first member. Movementof the at least one first member in this embodiment may be rotationalabout an axis of rotation such as where a rotor is used. Alternatively,movement of the at least one first member on application of anenergizing force may be linear movement as in the example of using acarriage as the second member(s).

In a further alternative embodiment, movement of the at least one firstmember on application of the energizing force may be linear movement. Inthis embodiment:

-   -   The at least one trigger member may be a pawl or arm shaped        member or members that are mechanically linked to a first member        that is a carriage which translates linearly on application of        the energizing force.    -   The at least one trigger member may be pivotally attached to the        carriage about a pivot axis offset from the line of motion of        the carriage.

Linear embodiments of this nature may be useful where the first memberor members move along a track such as in applications using longguidelines, e.g., a train carriage or a gondola and the above describeddevice acts to help brake the rate of movement of the carriage orgondola.

In a second aspect, there is provided a line dispensing deviceincorporating at least one device substantially as described above. Linedispensing devices such as auto belay devices are widely used to preventfalls in both recreational and industrial applications. In some cases,magnetically attracted relationships may be useful to tune the autobelay device characteristics. The at least one further member in thecase of a line dispensing device may be a spool of line coupled directlyor indirectly to the at least one first member. The external energizingforce imposed on the system in this embodiment may be caused by linebeing extended from or retracted onto the spool.

In a third aspect, there is provided a passenger seat restraintincorporating webbing for extending and retracting, the webbingoperatively coupled to at least one device substantially as describedabove. One example of a passenger seat restraint may be a seat belt usedin a vehicle such as a car. Seat belts are a critical safety feature andthe above described device may provide a useful alternative to existingdesigns particularly given the ability to tune the response in the widevariety of ways noted.

In a fourth aspect, there is provided a transmission drive incorporatingat least one device to engage a rotational drive substantially asdescribed above.

In a fifth aspect, there is provided a linear guided lifelineincorporating at least one device substantially as described above.

The above examples should not be seen as limiting since the devicesdescribed may be used for a wide variety of other applications,non-limiting examples including control of:

-   -   a rotor in a rotary turbine;    -   exercise equipment, e.g., rowing machines, epicyclic trainers;    -   roller-coasters and other amusement rides;    -   Elevator and escalator systems;    -   evacuation descenders and fire escape devices;    -   conveyer systems:    -   rotary drives in factory production facilities;    -   materials handling devices such as conveyer belts or a braking        device in a chute;    -   dynamic display signage to control the rate of change of        rotating signs;    -   roadside safety systems, e.g., the eddy current brake may be        connected in a system to provide crash attenuation though the        dissipation of energy via the brake;    -   seat belts in vehicles;    -   braking mechanisms for trolleys and carriages.

As noted above, one advantage of the above device includes the abilityto control the rate of movement prescribed by the kinematicrelationship. In addition, a further advantage of the device is to alsoinfluence the kinematic relationship once movement commences. Themagnitude of the resistance to movement may be varied in a consistentmanner as the members move or in a stepped or otherwise varied manner.Tuning in this way may have the effect of avoiding unwanted activationor slowing the speed of activation of, for example, a brake engagement.

The embodiments described above may also be said to broadly consist inthe parts, elements and features referred to or indicated in thespecification of the application, individually or collectively, and anyor all combinations of any two or more said parts, elements or features,and where specific integers are mentioned herein which have knownequivalents in the art to which the embodiments relates, such knownequivalents are deemed to be incorporated herein as of individually setforth,

Where specific integers are mentioned herein which have knownequivalents in the art to which this invention relates, such knownequivalents are deemed to be incorporated herein as if individually setforth.

WORKING EXAMPLES

The above described device is now described by reference to specificexamples.

For ease of description in the examples, only a single trigger memberand single first member are shown although it should be appreciated thatmultiple trigger and first members may be used.

Where described, a second member magnetic field through which thetrigger member(s) move and a latching member are generally shown forprolixity as continuous regions. The second member, (if present at all)may for example be a series of discrete magnets or even just one magnet.Similarly, the latching member (if present) may take on various shapesor surface contours.

Example 1

As shown in FIGS. 1 and 2, a kinematic relationship between a trigger 1and first member 2 is described. For ease of drawing, additional membersand member details have been removed.

In the Example, the trigger member 1 is a pawl or arm that is pivotallylinked to a first member 2 drawn as a rotor with part of the rotor arearemoved for clarity. The pivoting link provides a pivot axis of rotation3 around which the trigger member 1 can rotate relative to the firstmember 2 or vice versa. In this Example, the first member 2 rotates indirection X about rotor axis 4 when an energizing force is applied. Onapplication of the energizing force that rotates the rotor in directionX, the trigger member 1 will, through combination of centrifugal forcesand inertial forces, be urged to pivot about the pivot axis 3 so that apart of the trigger member 1 moves. The solid line image of the triggermember 1 shows the pawl in a resting or trigger position while thedotted line shows the pawl in a second position post movement 5 showingthe trigger member 1 rotating about the pivot axis 3 in direction Y.

As shown, the trigger member 1 and first member 2 are approximatelyadjacent each other and in a constrained kinematic relationship relativeto each other.

The trigger member 1 and first member 2 are in a magnetic relationship.As shown in FIGS. 1 and 2, the trigger member 1 includes a magneticelement 6. The magnetic element 6 may be a portion of the trigger member1. The magnetic element 6 may be a separate item (6 a in FIG. 2) slottedinto the trigger member 1 or hidden inside the trigger member 1 (notshown). On the first member 2 at a point complementary to the magneticelement 6 is a conductive region (shown as item 7 in FIG. 2). As shouldbe appreciated, the magnetic element 6 and conductive region 7 describedabove may be swapped so that the trigger member 2 contains theconductive region and the first member 2 contains the magnetic element.

The magnetic element may be the whole trigger member 1 or may havediffering shapes to that shown in FIGS. 1 and 2. Similarly, theconductive region 7 in the first member 2 may be the whole first member2 or parts of the first member 2.

In action, as the varying rate of motion occurs, at least onemagnetically induced flux results between the trigger member 1 and firstmember 2 thereby forming a magnetically induced eddy current forcebetween the members 1, 2 or a part thereof.

The magnetically induced eddy current force may act to resist relativemovement between the members 1, 2 and the at least one first member 2.The magnetic flux may be tuned by varying a number of characteristics ofthe arrangement including altering the magnetic element 6 and/orconductive region 7 size and positioning; altering the proximity of thetrigger and first members thereby altering the proximity of the magneticelement 6 and conductive region 7; and finally altering the geometryand/or magnetic/conductive properties of the magnetic element(s)6/conductive region(s) 7.

As shown in the Figures, the direction of the magnetically induced fluxis in a direction substantially orthogonal to the direction of motionbetween the trigger member 1 and the first member 2 and the members 1, 2lie in the same plane adjacent each other both at rest and duringmovement.

The embodiment described above may be integrated into a device similarto that described in US2012/0055740.

Example 2

Referring to FIG. 3, movement of the trigger member 1 may be linear inresponse to a rotational movement of the first member 2. As shown inFIG. 3, the trigger member 1 may be a rod, the rod slotting into a holeor indentation (not shown) in the first member 2. The rod 1 may includea magnetic element 6 (or conversely, a conductive region), the choice ofa magnetic element or conductive region depend on what the complementarypart is on the first member 2. When rotation of the first member 2occurs, the rod moves out of the hole or indentation in a lineartranslation shown as an arrow along direction Z in FIG. 3.

Example 3

FIGS. 4 and 5 illustrate an alternative embodiment where movement of thefirst member 2 occurs in a linear direction shown as arrow AA when anenergizing force is applied.

The trigger member 1 may be a pawl or arm shaped member or members (onepawl shown for clarity) that are mechanically linked to a first member 2that, in this example, is a carriage which translates linearly indirection AA on application of the energizing force along a surface ortrack 8.

In FIG. 4, the at least one trigger member 1 pivots about a pivot axis 3attached to the carriage 2 about a pivot axis 3 offset from thedirection of motion AA of the carriage. The trigger member 1 includes amagnetic element (or conductive region) 6 and the first member 2includes a complementary magnetic element or region (not shown) so thatthe trigger and first members 1, 2 are in a magnetic relationship.

FIG. 5 illustrates the same principle of a linear movement first member2, however in this case the trigger member 1 is a rod that moves in alinear manner as well, similar to that described in Example 2.

Linear embodiments of this nature may be useful where the first member 2or members move along a track 8 such as in applications use longguidelines, e.g., a train carriage or a gondola and the above describeddevice acts to help brake the rate of movement of the carriage orgondola.

Example 4

FIG. 6 illustrate yet further embodiments of devices using the abovedescribed magnetic relationship between a trigger and first member 1, 2.

The device may include at least one second member 10 (drawn for ease ofdescription as a shaded region) independent to the at least one firstmember 2, the second member 10 magnetically interacting with the triggermember 1 when the trigger member 1 moves away from the first member 2.This second member 10 may be a series of magnets or conductive regionsand, when the trigger member 1 moves into a space complementary to thesecond member 10, an eddy current induced force occurs between thetrigger 1 and second member 10.

The second member 10 may be stationary. Alternatively, the second member10 may move at a different relative speed to the trigger member 1 eitherin the same direction as the trigger member 1 (but different speed) or,in an opposing direction. The second member 10 may for example be aseries of magnets (not shown) outside and around the circumference ofthe first member 2.

Example 5

As shown in FIGS. 6 and 7, the trigger member 1 may engage with afurther latching member 20 upon movement of the trigger member 1 andfirst member 2. Engagement of the trigger member 1 and latching member20 may result in no further relative motion between the first member 2and the latching member 20. This latching member 20 may be useful toconstrain movement of the kinematic relationship. The engagement may bereleasable so as to re-set the device for further movement.

Example 6

FIGS. 8 and 9 illustrate a different approach using the second member10.

As shown in the Figures, the second member 10 is independent to thefirst member 2. The second member 10 magnetically interacts with thetrigger member 1 about part of the trigger member 1 that extends partlybeyond the overlapping region between the trigger member 1 and firstmember 2. The second member 10 may be a series of magnets or conductivemembers complementary to the trigger member 1 so as to cause a magneticflux interaction to occur when the second member 10 moves relative tothe trigger member 1.

With the trigger member 1 in a region complementary to the second member10, an energizing force on the second member 10 causes a magneticallyinduced eddy current force to occur between the trigger 1 and secondmembers 10 that encourages movement of the trigger member 1 relative tothe first member 2.

The first member 2 may be stationary and the trigger member 1 moves onapplication of the energizing force, the movement of the trigger member1 then induces a magnetic flux interaction between the trigger member 1and the first member 2.

As shown in FIG. 8, the kinematic relationship is prescribed by thetrigger member 1 moving pivotally relative to the first member 2.Alternatively, and as shown in FIG. 9, the kinematic relationship may beprescribed by the trigger member 1 moving via an independent lineartranslational path relative to the first member 2.

Aspects of the device have been described by way of example only and itshould be appreciated that modifications and additions may be madethereto without departing from the scope of the claims herein.

These and other changes can be made to the embodiments in light of theabove-detailed description. In general, in the following claims, theterms used should not be construed to limit the claims to the specificembodiments disclosed in the specification and the claims, but should beconstrued to include all possible embodiments along with the full scopeof equivalents to which such claims are entitled. Accordingly, theclaims are not limited by the disclosure.

What is claimed is:
 1. A clutch or brake comprising: at least one firstmember in a kinematic relationship with at least one further member toform a system, the system moving within a limited range of motion andwherein the system interacts when an external energizing force isimposed on the system causing the members to respond due to theirkinematic and dynamic characteristics and thereby creating relativemotion between the members; and at least one trigger member directlymechanically coupled to the at least one first member that moves withrespect to the first member in response to a pre-determined systemmovement and, when the at least one trigger member moves, the at leastone trigger member or a part thereof imposes a braking action on thesystem or a member or members thereof, by an interaction between thetrigger member and the further member, resisting relative movementbetween the trigger member and the further member; wherein the speedand/or intensity of the braking action imposed by the at least onetrigger member on the system or a member or members thereof iscontrolled by the at least one trigger member rate of movement withrespect to the first member and this rate of movement is in turngoverned by a magnetic flux interaction between the at least one triggermember or a part thereof and the at least one first member or a partthereof causing formation of a magnetically-induced eddy current forcebetween the at least one trigger member or a part thereof and the atleast one first member or a part thereof, the eddy current forceresisting movement of the trigger member with respect to the firstmember.
 2. The clutch or brake as claimed in claim 1 wherein the atleast one trigger member comprises a magnetic part or parts thatinteract with a conductor part or parts on the at least one first memberor wherein the at least one trigger member comprises a conductor part orparts that interact with a magnetic part or parts on the at least onefirst member.
 3. The clutch or brake as claimed in claim 1 wherein thekinematic relationship between the system movement and the at least onetrigger movement is a non-linear response.
 4. The clutch or brake asclaimed in claim 1 wherein the rate of movement of the at least onetrigger member relative to the first member slows as relative motionoccurs or the rate of movement of the at least one trigger memberrelative to the first member speeds up as relative motion occurs.
 5. Theclutch or brake as claimed in claim 1 wherein relative movement betweenthe system and the at least one trigger member is delayed until the pre-determined system movement occurs.
 6. The clutch or brake as claimed inclaim 1 wherein the system braking action imposed by the at least onetrigger member or a part thereof is caused by latching, friction,magnetic force interactions, or combinations thereof.
 7. The clutch orbrake as claimed in claim 1 wherein the rate at which the at least onetrigger member moves relative to the at least one first member is tunedby varying the resulting eddy current force between the at least onetrigger member and the at least one first member.
 8. The clutch or brakeas claimed in claim 7 wherein the magnetically induced eddy currentforce is tuned by varying at least one characteristic of the clutch orbrake selected from the group consisting of: a magnetic element surfacearea on or within the at least one trigger member or at least one firstmember; a conductive region on or within the at least one trigger memberor at least one first member; a proximity of at least one magneticelement and at least one conductive region on the at least one triggermember and at least one first member; a geometric and/or magneticproperty of the at least one magnetic element on or within the at leastone trigger member or at least one first member; and a geometric and/orelectrical property of the at least one conductive element on or withinthe at least one trigger member or at least one first member.
 9. Theclutch or brake as claimed in claim 1 wherein the trigger member movesdirectly due to the energizing force.
 10. The clutch or brake as claimedin claim 1 wherein the trigger member moves indirectly at least in partdue to the energizing force causing at least one additional mechanicalpart or force dynamic to move or interact with the trigger member andthereby subsequently causing motion of the trigger member.
 11. Theclutch or brake as claimed in claim 1 wherein static or dynamicpositional and/or strength adjustment of the point of action of the eddycurrent induced force is also completed by adjusting a position of themagnetic element or conductive region on the trigger member as thetrigger member or first member moves or adjusting a position of themagnetic element or conductive region on the first member as the triggermember or first member moves.
 12. The clutch or brake as claimed inclaim 1 wherein the at least one trigger member and the at least onefirst member or parts thereof are approximately adjacent to each other.13. The clutch or brake as claimed in claim 1 wherein the trigger memberis an arm-shaped member that rotates about an axis when thepre-determined system movement occurs.
 14. The clutch or brake asclaimed in claim 1 wherein the at least one trigger member is a rodshaped member that moves in a linear direction when the pre- determinedsystem movement occurs.
 15. The clutch or brake as claimed in claim 1wherein at least one second member is provided, the second member beingindependent to the at least one first member, and the second membermagnetically interacting with the at least one trigger member about atleast a part of the at least one trigger member outside an areaoverlapping the at least one first member.
 16. The clutch or brake asclaimed in claim 1 wherein the clutch or brake is incorporated within anapparatus selected from the group consisting of: a line-dispensingdevice wherein the at least one further member is a spool of linecoupled directly or indirectly to the at least one first member andwherein the external energizing force imposed on the system is caused byline being extended from or retracted onto the spool; a passenger seatrestraint; a transmission drive; and a linear guided lifeline.
 17. Theclutch or brake as claimed in claim 1, wherein the first member is arotor.
 18. The clutch or brake as claimed in claim 1, wherein the firstmember is a carriage.